It might be a useful addition if, when a user with a tag badge answers a question tagged with their tag badge, that that information be displayed visually near their badge.

ie, when Jon Skeet answers a question about C#, there will be a visual cue to indicate that he is, in fact, fairly well established in that topic.

That way, reputation information displayed near a user's info can be given domain-specific utility. ('Oh, this person has 100k rep but hasn't spent a lot of time on this topic' vs 'This person has 5k rep but seems specialized in this topic').

Obviously, we should be judging answers based on their accuracy and correctness, but the reputation gives us an indication as to how much 'benefit of the doubt' we should be giving on difficult-to-evaluate answers.

(There are two obvious ways to do this: The easier is to highlight their user info box in a different color to indicate the extra expertise; the other is to show the badge itself somehow, but that's a bigger change.)

Obviously, we should be judging answers based on their accuracy and correctness, but the reputation gives us an indication as to how much 'benefit of the doubt' we should be giving on difficult-to-evaluate answers.

I think the first part of your statement proves your request is not needed. If the answer is correct or useful, upvote it. If it's incorrect, or has serious problems, downvote (and comment). Or just comment and ask for corrections.

There's no need to upvote someone's answer because they're good in that tag. You're voting for the answer, not for the person.

If we were truly supposed to be rank-neutral, answers wouldn't display the reputation and the number of badges rewarded. My point is, this information could be made more relevant. Domain-specific knowledge in one area doesn't necessarily mean you'll have knowledge in another domain.
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YahelFeb 22 '11 at 1:04

That information is what makes up your profile. It's your "flair". It's used to give you an identity on the site, not for people to use to critique your answer.
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The Unhandled ExceptionMar 3 '11 at 20:34